When rotors look like this...

I don't believe in turning rotors. I replace with new if there's any question. I had 2 front rotors like that one in the pic thinner on one side. The Truck came that way. The shimmy when braking when they warmed up was terrible as the rotors warped when hot. New $20 rotors fixed it, but that's what happens when someone clueless turns your rotors.

I agree with the Dr. and with others that have posted - it's easier to replace. Rock auto, autopartsguru, etc. $20 vented rotors are always a better idea. What's it cost to turn a rotor anyway? $10?

Where do you guys find cheap rotors? The cheap made in China E36 M3 from Autozone/Murray's/etc are like 40 a pop, but I wasn't happy with their quality, I've only used them once, and was ready to switch back to OEM before I found out how cheap I could get the ATE stuff for.

captainzib wrote: Where do you guys find cheap rotors? The cheap made in China E36 M3 from Autozone/Murray's/etc are like 40 a pop, but I wasn't happy with their quality, I've only used them once, and was ready to switch back to OEM before I found out how cheap I could get the ATE stuff for.

Drive a Miata and then you can buy $18 brembo rotors.

rusnak_322 said: Drive a Miata and then you can buy $18 brembo rotors.

Or a crown vic...

I get mine off of rockauto. I just got pads and rotors for the escort for around $100 shipped. Halfway decent stuff, too.

Damn, rotors for my Camry are expensive. Now that ain't right.

Though I suppose bringin that fatass of a car to a halt does require some beefy brakes.

LS400 rotors are kinda pricy, but the ones for my RN Trucks were dirt cheap from JC Whitney. The Rolla ones were pretty reasonable from O'Reilley's.

Rock Auto is going to be a sponsor for our car show, Brits in the Ozarks. That's nice of them. They found us and offered stuff. I bought the upper ball joint for my Esprit from them a few weeks ago. Twenty bucks (last one in stock) beat the heck out of $150 at autozone.

I have a 50k mile 75 Chevy k10 4x4 truck undergoing a frame off resto. I took the 50k mile, never turned, rotors in to have them turned or replaced. My used rotors had MORE material left that the aftermarket new replacements at the parts store. I get pretty aggravated at what junk most replacement parts are these days.

Also, count me in the pool that does not turn/replace rotors at every pad change.

Rotors aren't always cheap either. In the last couple of years I've replaced them on a one ton dually, 1/2 ton 4x4 Suburban, and 03 Mach 1 Mustang. The Suburban's were cheap....the rest....not, but they did need to be replaced, so I bought new.

I replace em every brake job on cars that have hubless rotors. Sure I could swing by my uncles shop and turn them, but for what a rotor costs ME it's not worth it.

captainzib wrote: Where do you guys find cheap rotors? The cheap made in China E36 M3 from Autozone/Murray's/etc are like 40 a pop, but I wasn't happy with their quality, I've only used them once, and was ready to switch back to OEM before I found out how cheap I could get the ATE stuff for.

Go online find the cheapest price, you can, print it out, then go to advance auto parts, and ask them to price match.

I paid $17 each for rotors for my Miata at NAPA last week. Never had any issues with the quality of their brake parts.

Yea, drive a Saturn. Cost of ownership is hilariously cheap. $18 rotors is only the beginning. There's a reason I feel sorry for guys in BMWs and Porsches...

I will say that the $18 rotors warp if you look at them the wrong way...they last maybe 10K miles before the steering-wheel-shake-under-braking becomes probably pretty dangerous, but at $36 for the pair, who cares?

captainzib wrote: Damn, rotors for my Camry are expensive. Now that ain't right. Though I suppose bringin that fatass of a car to a halt does require some beefy brakes.

Get used to it. It costs me more to replace the rotors on my Celica than my entire suspension on the MX6 cost me.

But hey, i guess i can find solace in the fact that the brakes on the Celica are in a completely different universe than what's on the MX6.

Twin_Cam wrote: Yea, drive a Saturn. Cost of ownership is hilariously cheap. $18 rotors is only the beginning. There's a reason I feel sorry for guys in BMWs and Porsches...

Yeah, I pay $50 each for rotors for the 740iL. But then again, I end up with BMW brakes, not Saturn brakes AND they don't warp again in 10k miles. so... you pay $18 every 10k miles and I pay $50 every 50k miles. The BMW doesn't seem so expensive. Of course, you don't have to replace a radiator every 70k miles, so maybe it all evens out... But then again, I don't have to drive a Saturn...

captainzib wrote: Can they still be taken to a shop that'll turn em and then reused?

No. Rust destroys the bits.

if you find a place that will machine them, they don't care about their equipment and they'll probably do a crappy job.

Do this: Mount them on the car and drive them. After you burn the rust off, THEN take them off for machining.

porksboy wrote:

John Brown wrote: New rotors are always cheaper than a new spleen.

Yes, but do you replace the engine when you change the oil? How about the master cylinder and calipers when you flush the brake fluid?

Every time I run low on fuel, I buy a new car. Safety first.

I never turn or replace brake rotors unless they're heavily rusted from sitting, and even then, I drive them first.

Did you know that you're not supposed to replace pads and rotors at the same time? If you want to get that final couple percent, you need to break them in separately.

John Brown wrote: New rotors will always offer a better surface than machined or used units

This is only a case if you have someone who doesn't care doing the machining. Some people only do rough cuts and no final cuts, some people stop at the final cut and don't do a non-directional finish, some people don't clean the rotor surface afterwards.

A lot of people just throw the rotor onto the lathe without measuring runout, and this raises a valid point: How can anybody machine a rotor without having the car there? You can chuck a rotor into the lathe three times and get three different high spots. It is super critical to get out the dial indicator and find the high spot on the rotor as mounted in the car and then duplicate that in the lathe.

All that said, I've measured .016" runout (max is about .001") on new rotors, and I've seen surface finishes that look like they just used a Sawzall to carve a hunk of iron off of a 10" bar. New doesn't mean good.

And then new rotors usually need to be machined after use anyway, since they like to "twang" every now and then. Once machined after the twang, they won't warp again.

Chew on this: Much of pad break-in is transfer of material to the rotor. If the material is already there, then much of the break-in is already completed. If there's no brake pulsation, and you're not drastically changing pad composition, there is no reason to machine or replace.

i never turn rotors. if they need turned i buy new.

but i never replace unless they are warped or chewed up. the originals on my 91 caprice lasted to 149k before they gave up not due to wearing of the friction surface but because the vanes rusted away and the rotors split off the hub. need new rotors and calipers for the front of my dually, that just makes me ill. $100+ each rotor for the cheapest

127k on stock rotors for me. This is the last time for the rears though... last turning put them at minimum thickness.

200k+ on stock rotors on a Ranger for me. Never turned, still above min. thickness. I replace the pads with pads from the dealer, they give me a great discount and its only a few bucks more than premium parts store pads. I do drive a lot of highway miles.